Spreads in percentages NOt points

[Eddy-2d]

Why doesn't NinjaTrader allow us to set spreads as percentages of the bid/ask instead of just points in backtests? That would be much more representative of true trading costs.

[NinjaTrader_Bertrand]

Eddy, thanks for the suggestion - You refer to the Slippage box, correct?

We would normally advise to enter a representative avg value there.

[Eddy-2d]

Eddy, thanks for the suggestion - You refer to the Slippage box, correct?

We would normally advise to enter a representative avg value there.

Yes correct. Why would you advise the " representative avg value "?

[NinjaTrader_Bertrand]

Because those can vary, especially in FX spot markets...